URGENT SAFETY ISSUE: Gas Control Valve

My B-W propane water heater, about 22 years old, has gone through several thermocouples in the last few years. The techs installed a new pilot burner and tc recently and all was well till we came home from vacation Sunday night and found we had no hot water. I tried to relight, but it wouldn't stay lit, so cold shower Monday morning.

Techs came again and replaced the tc (yet again) but still couldn't re-light it, so it must be the valve. Since the heater is way past its life expectancy, I didn't want to spend any repair money on it, but I need a few days to decide what heater to get.

The tech removed a collar around where the tc attaches and pulled out two small wires. I'm not sure if he disconected them or what. Replaced the tc and then was able to re-light in the normal manner, giving me a reprieve.

What do those wires do? He said it's an extra safety feature which is "not important"! What is the likelihood of something bad happening? He wasn't able to explain it to me.

As a precaution while it's in this state, we're keeping the unit on pilot only, turning it on only when we shower. Don't want to turn the pilot off for fear of not being able to re-light. Meantime, I'm researching heaters, and considering replacing heater AND furnace with a combination unit, so I'd like some more time! Is this safe or not?

Those wires are part of a high temperature limit circuit. Bypassing that feature is potentially VERY dangerous. I am sure that the gas valve manufacturer specifies that if that limit is tripped, or malfunctioning in any way, the valve MUST be replaced.

You could call a tech line at the water heater manufacturer, or the gas valve maker, to confirm the function of those wires, and how to proceed.

Now, I would think twice about spending any more money on a 22 year old gas water heater.

Thanks guys. I had a rather dim suspicion it might be a temperature limit circuit.

I agree 500% about disabling safety features - that's why I came to this forum. As a Navy employee, I often read an aviation safety pub that occasionally hits on such things. I'll try to contact B-W, but knowing now what it is, I think I feel safe if I always turn it back to pilot after a shower. And my wife knows how to do it too. Hopefully, it'll only be a week or so before we get a whole new combo water/space heater installed. Or if we get sticker shocked on that, then just a new water heater. We have two HVAC companies coming tomorrow to give us quotes.

Thanks again!

Postscript: Just talked to a very helpful Bradford White tech rep. He agrees completely with living with the safety disabled if I turn it to pilot after showering.